An implementation of the W3c Extended Log File Format. See http://www.w3.org/TR/WD-logfile.html for more information about the format. The following fields are supported:

• c-dns: Client hostname (or ip address if enableLookups for the connector is false)
• c-ip: Client ip address
• bytes: bytes served
• cs-method: request method
• cs-uri: The full uri requested
• cs-uri-query: The query string
• cs-uri-stem: The uri without query string
• date: The date in yyyy-mm-dd format for GMT
• s-dns: The server dns entry
• s-ip: The server ip address
• cs(XXX): The value of header XXX from client to server
• sc(XXX): The value of header XXX from server to client
• sc-status: The status code
• time: Time the request was served
• time-taken: Time (in seconds) taken to serve the request
• x-threadname: Current request thread name (can compare later with stacktraces)
• x-A(XXX): Pull XXX attribute from the servlet context
• x-C(XXX): Pull the cookie(s) of the name XXX
• x-O(XXX): Pull the all response header values XXX
• x-R(XXX): Pull XXX attribute from the servlet request
• x-S(XXX): Pull XXX attribute from the session
• x-P(...): Call request.getParameter(...) and URLencode it. Helpful to capture certain POST parameters.
• For any of the x-H(...) the following method will be called from the HttpServletRequest object
• x-H(authType): getAuthType
• x-H(characterEncoding): getCharacterEncoding
• x-H(contentLength): getContentLength
• x-H(locale): getLocale
• x-H(protocol): getProtocol
• x-H(remoteUser): getRemoteUser
• x-H(requestedSessionId): getRequestedSessionId
• x-H(requestedSessionIdFromCookie): isRequestedSessionIdFromCookie
• x-H(requestedSessionIdValid): isRequestedSessionIdValid
• x-H(scheme): getScheme
• x-H(secure): isSecure

Log rotation can be on or off. This is dictated by the rotatable property.

For UNIX users, another field called checkExists is also available. If set to true, the log file's existence will be checked before each logging. This way an external log rotator can move the file somewhere and Tomcat will start with a new file.

For JMX junkies, a public method called rotate has been made available to allow you to tell this instance to move the existing log file to somewhere else and start writing a new log file.

Conditional logging is also supported. This can be done with the condition property. If the value returned from ServletRequest.getAttribute(condition) yields a non-null value, the logging will be skipped.

For extended attributes coming from a getAttribute() call, it is you responsibility to ensure there are no newline or control characters.